Evaluation of non-isothermal thermal degradation kinetics of lavender essential oil (Lavandula angustifolia)

Lavender essential oil (EO) is one of the most important substances extracted from the flower of Lavandula angustifolia Mill endowed with several pharmacological activities such as antifungal, anti-inmutagenic, muscle relaxant activity and others that makes the study of the thermal degradation of this substance essential. Thus, this work aimed to evaluate the non-isothermal degradation kinetics of lavender essential oil (Lavandula angustifolia) of commercial origin using the methods proposed by Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS). Antimicrobial activity and hemolytic potential were also determined. Therefore, three thermogravimetric curves were constructed at different heating rates (5, 10 and 20 degrees C min(-1)) in a temperature range between 30 and 600 degrees C, using the FWO and KAS methods to determine the energy activation (E-a). In the evaluation of the antimicrobial activity, the minimum inhibitory concentration. Minimum bactericidal/fungicide concentration was determined against the strains of S. aureus. E. coli. P. aeruginosa and C. albicans. Finally, the in vitro hemolytic activity test was performed, using triton x-100 as a positive control and saline as a negative control. The EO presented only one thermal event corresponding to total mass loss, between 120 and 149 degrees C. The E-a found by the FWA and KAS methods was 49.97 kJ mol(-1) and 46.36 kJ mol(-1), respectively, and no relevant differences were found. However, there were several complex steps in the decomposition reaction and a considerable antimicrobial activity against the tested strains, not being detected a high index of hemolytic activity.

Automated summary

This study aimed to evaluate the non-isothermal degradation kinetics of commercial lavender essential oil and determine its antimicrobial activity and hemolytic potential. The results showed that lavender essential oil exhibited strong pharmacological activity and antimicrobial properties, with multiple complex steps in the thermal degradation process.